// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "media/base/decoder_buffer.h"

namespace media {

// Allocates a block of memory which is padded for use with the SIMD
// optimizations used by FFmpeg.
static uint8_t* AllocateFFmpegSafeBlock(size_t size)
{
    uint8_t* const block = reinterpret_cast<uint8_t*>(base::AlignedAlloc(
        size + DecoderBuffer::kPaddingSize, DecoderBuffer::kAlignmentSize));
    memset(block + size, 0, DecoderBuffer::kPaddingSize);
    return block;
}

DecoderBuffer::DecoderBuffer(size_t size)
    : size_(size)
    , side_data_size_(0)
    , is_key_frame_(false)
{
    Initialize();
}

DecoderBuffer::DecoderBuffer(const uint8_t* data,
    size_t size,
    const uint8_t* side_data,
    size_t side_data_size)
    : size_(size)
    , side_data_size_(side_data_size)
    , is_key_frame_(false)
{
    if (!data) {
        CHECK_EQ(size_, 0u);
        CHECK(!side_data);
        return;
    }

    Initialize();

    memcpy(data_.get(), data, size_);

    if (!side_data) {
        CHECK_EQ(side_data_size, 0u);
        return;
    }

    DCHECK_GT(side_data_size_, 0u);
    memcpy(side_data_.get(), side_data, side_data_size_);
}

DecoderBuffer::~DecoderBuffer() { }

void DecoderBuffer::Initialize()
{
    data_.reset(AllocateFFmpegSafeBlock(size_));
    if (side_data_size_ > 0)
        side_data_.reset(AllocateFFmpegSafeBlock(side_data_size_));
    splice_timestamp_ = kNoTimestamp;
}

// static
scoped_refptr<DecoderBuffer> DecoderBuffer::CopyFrom(const uint8_t* data,
    size_t data_size)
{
    // If you hit this CHECK you likely have a bug in a demuxer. Go fix it.
    CHECK(data);
    return make_scoped_refptr(new DecoderBuffer(data, data_size, NULL, 0));
}

// static
scoped_refptr<DecoderBuffer> DecoderBuffer::CopyFrom(const uint8_t* data,
    size_t data_size,
    const uint8_t* side_data,
    size_t side_data_size)
{
    // If you hit this CHECK you likely have a bug in a demuxer. Go fix it.
    CHECK(data);
    CHECK(side_data);
    return make_scoped_refptr(new DecoderBuffer(data, data_size,
        side_data, side_data_size));
}

// static
scoped_refptr<DecoderBuffer> DecoderBuffer::CreateEOSBuffer()
{
    return make_scoped_refptr(new DecoderBuffer(NULL, 0, NULL, 0));
}

bool DecoderBuffer::MatchesForTesting(const DecoderBuffer& buffer) const
{
    if (end_of_stream() != buffer.end_of_stream())
        return false;

    // It is illegal to call any member function if eos is true.
    if (end_of_stream())
        return true;

    if (timestamp() != buffer.timestamp() || duration() != buffer.duration() || is_key_frame() != buffer.is_key_frame() || splice_timestamp() != buffer.splice_timestamp() || discard_padding() != buffer.discard_padding() || data_size() != buffer.data_size() || side_data_size() != buffer.side_data_size()) {
        return false;
    }

    if (memcmp(data(), buffer.data(), data_size()) != 0 || memcmp(side_data(), buffer.side_data(), side_data_size()) != 0) {
        return false;
    }

    if ((decrypt_config() == nullptr) != (buffer.decrypt_config() == nullptr))
        return false;

    return decrypt_config() ? decrypt_config()->Matches(*buffer.decrypt_config())
                            : true;
}

std::string DecoderBuffer::AsHumanReadableString() const
{
    if (end_of_stream()) {
        return "end of stream";
    }

    std::ostringstream s;
    s << "timestamp: " << timestamp_.InMicroseconds()
      << " duration: " << duration_.InMicroseconds()
      << " size: " << size_
      << " side_data_size: " << side_data_size_
      << " is_key_frame: " << is_key_frame_
      << " encrypted: " << (decrypt_config_ != NULL)
      << " discard_padding (ms): (" << discard_padding_.first.InMilliseconds()
      << ", " << discard_padding_.second.InMilliseconds() << ")";

    if (decrypt_config_)
        s << " decrypt:" << (*decrypt_config_);

    return s.str();
}

void DecoderBuffer::set_timestamp(base::TimeDelta timestamp)
{
    DCHECK(!end_of_stream());
    timestamp_ = timestamp;
}

void DecoderBuffer::CopySideDataFrom(const uint8_t* side_data,
    size_t side_data_size)
{
    if (side_data_size > 0) {
        side_data_size_ = side_data_size;
        side_data_.reset(AllocateFFmpegSafeBlock(side_data_size_));
        memcpy(side_data_.get(), side_data, side_data_size_);
    } else {
        side_data_.reset();
        side_data_size_ = 0;
    }
}

} // namespace media
